Founder of Health Rising and Phoenix Rising
Chris Kresser: OK, so I’m sure some of you have seen articles in the mainstream media about this or have seen some chatter in social media or whatnot, and it is true that some studies show that vegetarian diets are better for the microbiome and eating meat is associated with unfavorable changes in the microbiome. But once again, you have to understand the issues with most of this kind of research.
To get a much more detailed discussion of this, go back a few podcasts and listen to theresearch 101 show that we did where we covered all of these issues much more extensively, but most of these studies are just comparing two groups of people. They’re comparing meat eaters and vegetarians, and then they look at the microbiome in each group and then they come to some conclusion where they say, OK, people who eat meat generally have a worse microbiome than vegetarians.
The problem with drawing that conclusion is that we know from other studies that the average meat eater does a lot of things differently than the average vegetarian. They eat fewer vegetables and fresh fruits. They don’t exercise as much. They tend to smoke more. They consume more alcohol. They engage in all kinds of other behaviors that can adversely affect the microbiome, and studies do try to control for some of those other confounding factors, but they can never control for all of them.
What we can learn from these studies is only that the average person who eats red meat has a disrupted gut microbiome compared to the average vegetarian. That’s the only thing a study like that can tell us. It doesn’t tell us whether it’s because of the meat or because it’s the buns that they’re eating, like, the hotdog buns and hamburger buns around the meat, or it’s the sugar, or it’s the other crap that they’re eating, or it’s a lack of exercise, or it’s that they smoke more frequently.
Those other factors are, more than likely, what are causing this difference. If you extend that, of course, it doesn’t mean that a person who eats red meat that is also eating a lot of fresh fruits and vegetables and fermented fibers, fermented foods, that isn’t eating a lot of refined sugar and industrial seed oils, that is exercising and sleeping and taking care of themselves is going to have an inferior microbiome compared to someone that’s doing all those things and not eating meat. There is no study that I’ve seen that has come to that conclusion.